deposit reserve ratio（存款准备金）的英文解释最好能用英文多说明一下它的作用之类再问一下bull market（牛市）,bear market （熊市）的详细一点英文解释,急用

Deposit reserve ration, also known as required reserve ration, is a bank regulation that sets the minimum reserves each bank must hold to customer deposits and notes. These reserves are designed to satisfy withdrawal demands, and would normally be in the form of fiat currency stored in a bank vault (vault cash), or with a central bank.
The reserve ratio is sometimes used as a tool in monetary policy, influencing the country's economy, borrowing, and interest rates.
The ratio of required reserves to deposits ranges from 3% to 12% for transaction accounts such as checking accounts and Negotiable Order of Withdrawal (NOW) accounts, and up to 3% for time deposits (certificates of deposit).
Reserve requirements are one of the key tools in deciding how much money banks can lend, thus setting the pace at which the nation's money supply and economy grow. The higher the reserve requirement, the tighter the money-and therefore the slower the economic growth.
A bull market tends to be associated with increasing investor confidence, motivating investors to buy in anticipation of further capital gains. The longest and most famous bull market was in the 1990s when the U.S. and many other global financial markets grew at their fastest pace ever